Contact roll for electroplating



W. E. WINTERHALTER CONTACT ROLL FOR ELECTROPLATING Oct. 17, 1950 Filed Harch 7, 1946 QENQEN.

4 Sheets-Sheet 1 INVE NTOR: IV/ZZMM W/vmmzma I ms ATTORNEY.

Oct. 17, 1950 w. E. \ININTERYHALTER 2,526,312

CONTACT ROLL FOR ELECTROPLATING Filed March 7, 1946 4 Sheets-Sheet 2 a: FIEA. 7a

FEE-

INVENTOR: W/AA/AW W/vrm/m 75E,

HIS ATTORNEY.

CONTACT ROLL FOR ELECTROPLATING 4 Sheets-Sheet 3 Filed larch 'r, 1946 HIS ATTORNEY.

w JMQZZA/L 7 g y INVENTORZ 1 W/ZZ/fl/V f. VV/NTZPHMTEQ 1950 w. E. WINTERHALTER 2,526,312

CONTACT ROLL FOR ELECTROPLATING Filed larch '7, 1946 4 SheetsSheet 4 w FIEAD- a! 6i fi/ M u up w X15 5/ INVENTOR:

l V/ALMM E. W/NTEEf/fll 70a HIS ATTORNEY.

Patented Oct. 17, 1950 CONTACT ROLL FOR ELECTROPLATING V William E. Winterhalter, Coshocton, Ohio, as-

signor to Carnegie-Illinois Steel Corporation, corporation of New Jersey Application March 7, 1946, Serial No. 652,626

7 Claims.

Many processes have been developed for electroplating rapidly moving metallic strip with a dissimilar metal. In such operations it is customary to electrically energize the strip of base metal that receives the plating by passing the continuously moving strip over and around contact rolls that are connected electrically to a suitable-source of current which energizes the contact rolls, the latter conducting the current to the strip being plated for cathodically energizing the strip as the strip passes into the plating electrolyte from the contact rolls. These rolls outlet ports. The outlet ort is provided with a short pipe to maintain the interior of the roll substantially full of water. The shaft is solid in cross section between the inlet and the outlet pipe, and ports are provided through the conductor reinforcing webs for passage of the cooling water.

have a dual function in fact, for they not only make the moving strip the cathode in the plating cells by virtue of the electrical contact of the strip tion and to scoring action on the part of the rapidly moving strip; they handle heavy currents,

and therefore must be protected from overheating; they must possess a high degree of mechanical strength.

Customarily, the contact rolls of the type referred to herein comprise a hollow cylindrical shell of a metal of good electrical conductivity, which shell is mounted on a hollow shaft which also is of a metal of good electrical conductivity, copper being the metal usually employed for the roll shell and, for the shaft, because of its high electrical and thermal conductivity. The copper roll shell is connected to the shaft by means of end closure members of high strength metal, such as steel, these closure members being relatively heavy castings that are welded to the shaft and to the roll shell. Additionally, the roll is reinforced interiorly by copper webs or discs, which are suitably spaced along the shaft and brazed to the shaft and to the inner surface of the roll shell. These webs not only reinforce the roll shell, but also form the electrical conductors for electrically connecting the shaft and the roll shell. Current is supplied to the roll through brushes engaging the shaft.

In order to prevent the roll from becoming I Considerable difficulty has been experienced in the assembling of these contact rolls in accordance with prior practice, especially in obtaining satisfactory brazing due to the accelerated flow of heat in the various component parts during brazing, resulting in undetected brazing defects inside the roll, with consequent unsatisfactory distribution ofcurrent and in some cases structural failure. The brazing also results in heating the copper roll body to a degree where portions of the surface become slightly annealed, thereby causing undesirable variations in the electrical characteristics around the circumference of the roll. Also, the presence of the cooling water which customarily substantially fills the roll tends to render the roll unbalanced and adds to the weight of the roll.

It will be seen from the foregoing that the present invention relates to an improved mechanical and electrical construction of-a combined conveyor and contact roll adapted to make metallic strip or wire an electrode in the plating cell, and to a simplified and more efficient pro.- cedure for assembling this improved construction.

More specifically, the present invention has for one of its objects to provide a conductor, or contact, roll which can be finish assembled readily by a pressure fit without brazed connections between the roll body and the interior web mem'-,

bers, and without welded connections between the roll body and the steel and castings.

A further object of the invention is to provide a conductor roll which has uniform electrical connections throughout.

A still further object of the invention is to provide a conductor roll provided with more efficient cooling means than heretofore, with attendant reduction in the weight of the roll and improved electrical properties.

Further objects of the invention will become apparent as the description proceeds, and the features of novelty will be set forth in particularity in the appended claims,

The invention will be understood more readily by reference to the accompanying drawings, wherein:

Figure 1 represents a longitudinal sectional elevation of an embodiment of a conductor, or contact, roll embodying the improvements of the present invention;

Figure 2 is a transverse sectional elevation taken on the line IIII of Figure 1;

Figure 3 is a sectional elevation taken on the line IIIIII of Figure 2;

Figure 4 is a longitudinal sectional elevation through a modified construction of contact roll;

Figure 5 is a longitudinal sectional elevation of a further modified construction of improved roll;

Figure 6 is a longitudinal sectional elevation of a still further modified construction of a contact roll;

Figure 7 is an enlarged transverse sectional elevation of the roll of Figure 6, the view being taken on the line VII-VII of Figure 6;

Figure 8 is an enlarged longitudinal half-section taken on the line VIII-VIII of Figure 7;

Figure 9 is a diagrammatic sectional elevation showing a portion of an electroplating line employing the contact rolls of the present invention, the rolls being shown diagrammatically with parts thereof omitted for clarity; and

Figure 10 is a diagrammatic showing of the apparatus illustrated in Figure 9, the view being taken on the line X--X of Figure 9.

Referring more particularly to the drawings,

and first to Figures 1 and 2, reference character A represents a hollow shaft assembly, which, for convenience of assembly, is shown as being com posed of two parts Ill and IDA, these parts or sections being complementary, the shaft section [0 being provided with a shank l 2 that is received in a recess I4 in shaft section Illa. A bore l8, Ilia passes longitudinally through the shaft sections, the bore parts l6 and Ilia being in register when the shaft sections In and Illa are assembled. Because of the necessity of having the shaft A of high electrical and heat conductivity, it preferably is made of copper, although it is not necessarily so limited. The sections I0 and Illa are welded together as indicated at l8 to form a rigid and unitary structure.

Brazed to the shaft A are circular web members 20, the web members being spaced suitably along the shaft A. The brazed unions between the web members 20 and shaft A are indicated at 22. The web members 20 are similar in diameter and thickness. In order to provide maximum heat and electrical conductivity, the'web members 20 preferably are made from copper.

These web members 20 are reinforced by spacer To the outer surfaces of the webs 20 are brazed,'

as shown at 2|, circular rings 28, which project substantially at right angles with the webs 20, as shown. These rings are preferably made of copper, in order to afford maximum heat and electrical conduction, and they are tapered on their inner side 30 from one extremity to the point of contact with the web members 20, and at the extremity of their outer surface 30a, and after being brazed to the web members 20, the projecting portions of the rings 28 are split into a number of segments 32, of equal width, as indicated by slots 33, Figure 2.

The web members 20 have loosely bolted to them through bolts 34, a clamping ring 36. These clamping rings are positioned between the web members 20 and the end of the roll assembly that is nearer thereto, the clamping rings 36 being adapted to be moved into clamping engagement with the web members 20, or released therefrom, by suitable actuation of the nuts 38 on the bolts 34. These clamping rings 36 have tapered peripheries, and are mounted on the bolts 34 with their smaller outside diameter facing the webs 20.

The tapered segmented rings 28 have their outside diameter closely conforming to the inside diameter of the roll body 40, which is slipped over the above-described assembly, whereby after proper centering of the roll body relative to the segmented rings 28 and the webs 20, the bolts 34 are tightened by proper rotation of nuts'38, thus drawing the clamping rings 36 towards the web members 20, thus exerting a powerful wedge action against the segments 32 of the segmented rings 28.

Roll end castings are provided, which are indicated at 42. These are relatively heavy castings, preferably of steel for strength, and they are designed to tightly engage the inner wall of the roll body 40 with a press fit. The end castings 42 are adapted to seat against an inner shoulder 44 of the roll body as shown and are provided with a recess 46 around the shaft, the recesses 46 beingfilled with a yieldable material 48. This material engages shoulders 53 on the shaft sections In and Ilia, being adapted to yield by any further in-movement of the end castings responsively to these end castings seating against the shoulders 44.

While welds and brazing have been mentioned above specifically as the uniting means for various parts of the assembly as described and shown, it is to be understood that the joining of the parts by welding is not a necessary limitation, as other rigid joining means may be employed, such as preformed silver solder or phosphorus-copper strip, for example.

The roll is mounted for service in suitable bearings, as indicated on Figure 9, on the top of an electrolytic cell 54. Current is supplied to the shaft from a suitable'source of direct current (not shown) by means of brushes or other electrical connections (not shown). While some of the current will pass to the surface of the roll by way of the hub members 56 and end castings 42, the major part of the current travels along the shaft A and web members 20 to the surface of the roll, whereby continuously moving strip is energized by contact with the roll surface and made an electrode, i. e. cathode, in the cell for receiving a plating of metal from the electrolyte 60. The cathodically energized strip passes between anodes 62 in the cell and around insulating sink rolls at the bottom of the cell, as shown at 64 (see Figure 9), and receives a plating of metal as it passes through the cell, at speeds which may be up to several hundred feet per minute.

In view of the conditions of service, the roll surface that contacts the strip may be made of a hard, wear and corrosion-resistant metal, such as chromium, not shown.

It will be seen from Figures 1, 2 and 3, that the web members 20 and the clamping rings 36 are provided with registering holes 86 and 68,

respectively, which form communications between the successive compartments in the roll defined by the web members 29 and clamping rings 99. Cold water is continuously passed through the shaft A while the roll is in service, the registering bore sections I6, I6a forming a passage for this water. For this purpose, one end of the shaft is connected to a supply of cold water, the

4 bolts I4 may be made of suitable material such other end of the shaft being connected to an outsame and the manner in which these castings are,

fitted into the roll body, and consequently do not need further discussion.

The same applies to the constructions shown in Figures 5 and 6. v

Referring toFigure 4, copper web members 19 are secured to the shaft by welding, soldering,

or brazing. The web members I9 preferably are a made of copper, and are reinforced by the hollow bars 12 which extend between the web members and form sleeves for through-bolts 14 having nuts I6 threaded thereon. The copper webs I9 have their peripheries tapered for engaging the ta- 4 pered rings 18 in close relation. These rings 18 are similar to the previously-described rings 28, and are divided into equal'segments 89, as described in connection with rings 28, there being, for example, twelve segments. The peripheries of the webs I9 are united rigidly to the segmented rings 18, by welding, soldering, and brazing. The roll body is slipped over these rings, the outside diameter of the segmented rings 18 being substantially the inside diameter of the roll body.

Clamping pressure between the segmented rings 18 and the inside of the roll body is effected by the use-0f individual wedges 82, one of which is provided for each segment 89 of the segmented rin 18, the mounting and operation of which wedges are similar to the detailed showing of Figure 8.

As will be seen from .Figure 4, each wedge 82 is slidably mounted on a bracket 84, a series of such brackets being welded, or otherwise rigidly secured, to the web members I9 on the sides of the web members that face towards the ends of the roll. The top of each wedge 82 preferably is formed arcuately and bears against the underside of the tapered segmented rings 18 so as to closely engage the rings at the thinnest portions thereof. Through-bolts I4 are passed through these wedges which move responsively to actuation of the nuts I6, inward movement of these nuts 16 causing the wedges 82 to exert a powerful squeezing force on the segments 89 of the rings I8, thereby clamping the rings tightly against the roll body.

The hollow bars 12 may be formed of a light, strong metal, such as an aluminum alloy. The wedges 82 and brackets 84 may be formed of the same material. This is merely illustrative and explanatory with reference to the use of aluminum alloys for the parts of the construction that are thus-specifically designated. The throughas stainless steel, for example.

In the modification of Figure 5, theinterior of the roll body and the shaft are modified in contour by providing the interior of the roll body with a restricted, or thickened, portion 88. the sides of which are tapered oppositely, as shown at 89, and thelshaft has a correspondingly enlarged section 99 having oppositely tapered ends 9|, the tapers being opposite to the tapers of the restricted portion of the roll body. The copper webs 92 have the complementary tapered peripheries 94, which engage the tapered sides 89 of the restricted portion 88 of the roll body. Through-bolts 96 extend through the webs 92, each bolt being provided with nuts 98 which engage the outer surfaces of the webs 92, tightening of the nuts 99 urging the webs 92 against the tapers on the inner surface of the roll, thereby clamping the copper webs against the roll body. The shaft is made of two similar sections threadedly united, as described above.

Figure 6 shows a modification similar to Figure 4, except for the substitution of stove bolts I99 for the through-bolts, these stove bolts extending through each of the copper webs I92 and the individual wedges I94 that are slotted as shown in Figure 7 to receive the mounting brackets I96, and are movable on the brackets I96, which are welded or otherwise rigidly secured to webs I92. These wedges I94 have an arcuate surface I98 (see Figure 8) that engages the tapering segments II9 of segmented rings H2. These segmented rings are welded, or otherwise united rigidly to the periphery of the webs I92. Clamping movement of the wedges is effected by manipulation of a nut II4 that is mounted on each of the stove bolts. As will be seen from Figure 8, the stove bolts pass through the respective wedges, forward movements of the nuts II4 along threads II6 of the bolts I99 forcing the wedges against the tapered surface of the segments II9, thereby producing a powerful clamping action of the wedges I94 against the 5 segments I I9 of the segmented rings II2, thereby tightly clamping the roll body in position.

Ashas been described above, the roll assembly is provided with a hollow shaft and end castings having a press fit in the roll shell as described above. Lock washers III are provided on bolts I99 to prevent accidental displacement of the nuts II4 from adjusted position.

These rolls are mounted as indicated schematically in Figures 9 and 10, which are shown as being representative of the mountings of rolls of the type described herein. It will be understood that in Figures 9 and 10, parts of the present roll structure that are not required for illustrating how the rolls are mounted, have been omitted from the views.

In accordance with Figure 9, there is shown a series of such rolls, these being indicated at H8, the shafts I29 of which are mounted in suitable bearings on any convenient mounting, such as for example, in bearings I24 that are shown as being mounted on I-beams I26, which run above, and parallel to, the electrolytic cells 54. In these cells 54, there are suspended a plurality of anodes 62, that hang from a bus bar I32, the strip I34 that is being electroplated and which has been energized cathodically by contact with rolls II8, passing between the anodes for receiving the plating on both sides of the rapidly moving strip. At the bottom of the electrolytic cells is an insulating sink roll 84 under and around which the strip passes. Bus bar I32 is connected to current supply leads I38 that are mounted on lateral flanges I 40 along the cells, and insulated therefrom, as indicated at I42. I

The contact rolls .II8 are suitably energized through leads I that preferably connect with suitable contacts to drum type collectors pressed onto each end of the shaft on the outboard side of the bearings, as will be well understood, although the leads may connect with brushes such as shown at I45 that engage the roll in any manner, such as through current collector plates I48. Such drum type collectors facilitate the handling of high currents, while their location is removed from severe electrolyte saturation with consequently lower leakage current, and insulation maintenance.

Sink rolls 64 are shown as mounted on shafts such as designated at I". These shafts pass through the cell walls and revolve in bearings I 50 on I-beams I52 laterally disposed relatively to the cells, along the bottoms thereof, as shown. Corresponding I-beams I54 along the tops of the cells serve as mountings for the contact lead bars I38. These bars are shown diagrammatically as receiving current from conductors I56 that are connected to a suitable current supply, not shown.

Itwill be understood also that the contact rolls of the invention may be used to energize the strip anodically, as where the strip is to be an anode for electrolytic cleaning. In fact, commercial electrolytic tinning lines include such contact rolls which make the strip anodic in the cleaning section of the line.

From the foregoing, it. is apparent that the improved construction of the present invention is adapted to be incorporated in various electrolytic embodiments, and that the construction of the present improved contact roll itself is subject to various modifications without departing from the inventive concept, and accordingly it will be understood that it is intended and desired to embrace within the scope of this invention such modifications and changes as may be necessary to adapt it to varying conditions and uses, as defined by the appended claims.

I claim:

1. Apparatus for electroplating a non-ferrous metal on a rapidly moving ferrous strip, which comprises a combined conveyor and electrical contact roll around which the rapidly moving strip passes in contact therewith, the said contact roll receiving current from a source therecf and cathodically energizing the strip as the strip passes through an electroplatin bath, the said roll comprising a closed hollow tubular member defining a roll body of high electrical and thermal conductivity, a hollow shaft for the roll, web members mounted on the shaft dividing the roll interiorly into sections, the said members being of high electrical and thermal conductivity, a tapered segmented ring peripherally secured to each web member, and wedges and screw threaded means for exerting expanding pressure on the segments of said rings for imparting pressure on the segments of the clamping rings for clamping the roll body to the web members.

2. Apparatus for electroplating a rapidly moving metallic strip with a dissimilar metal, which comprises a combined conveyor and electrical roll comprising a hollow tubular roll body, a hollow shaft adapted to pass cooling water therethrough, web members mounted on the shaft integrally therewith and extending radially from the shaft, a tapered ring peripherally secured to each web member and defining a segmented flange extending therefrom at substantially right angles, wedges and screw threaded means for expanding the segments of the segmented flanges against the roll body in a pressure-clamping flt therewith, end closure members for closing the roll body, and means for locking the screw threaded means in adjusted position for maintaining'the said segments rigidly expanded between the said wedges and the roll body.

3. Apparatus for electroplating a rapidly moving metallic strip with a dissimilar metal, which comprises a combined conveyor and electrical contact roll connected to a supply of current, the said strip making electrical contact with the roll by passing over and around the roll, the said roll comprising a hollow tubular roll body, a hollow shaft adapted to pass cooling water therethrough, web members mounted on the shaft extending radially therefrom in spaced relation, spacing means intermediate the web members holding the web members in rigid spaced relation, a ring peripherally secured to each web member, and extending at substantially right angles from the web members and defining flanges having an outside diameter closely conformin to the inside diameter of the tubular roll body, said rings being tapered on their underside from the web members toward their free edges, the said flanges being divided into a plurality of segments of substantially equal widths, tapered wedge plates, bolts mounting the wedge plates on the web members with the sides of the wedge plates having the smaller outside diameters facing the web members, nut means on the bolts adapted to press the wedge plates against the flanges in clamping pressure, clampin of the wedge plates against the flanges causing the wedge plates to expand the segments against the roll body for clampin the roll body to the web members, and closure means for each end of the roll body having a tight press fit in the roll body and around the shaft for rigidly closing the ends of the roll body.

4. Apparatus for electroplating a rapidly moving metallic strip with a dissimilar metal, which comprises a combined conveyor and electrical contact roll connected to a supply of current, the said strip making electrical contact with the roll by passing over and around the roll, the said roll comprising a hollow tubular roll body, a hollow shaft adapted to pass cooling water therethrough, web members on the shaft extending radially therefrom in spaced relation relative to each other, spacing means connecting the web members for supporting the web members in rigid spaced relation, a ring peripherally secured to each web member and extending at substantial'y right angles from the web members and defining flanges having an outside diameter closely conforming to the inside diameter of the tubular roll body, said rings being tapered on their underside from the web members toward their free edges, the said flanges being divided into a plurality of segments of substantially equal widths, a plurality of individual wedge members adjustably mounted on the web members, mounting instrumentalities for the wedge members including supporting brackets secured to the web members peripherally thereof, bolts passing through the web members and wedge members, the said wedge members having a surface engaging the segments of said rings for expanding the said segments against the tubular-body member responsively to clamping movement of the wedge members towards the web members, and nuts on the bolts engaging the said wedge members whereby tightening the nuts on the bolts forces the wedges towards the web members, thereby expanding the said segments and clamping the segments against the roll body.

5. Apparatus for electroplating a rapidly moving metallic strip with a dissimilar metal, which comprises a combined conveyor and electrical contact roll connected to a supply of current, the said strip making electrical contact with the roll by passing over and around the roll, the said roll comprising a hollow tubular roll body, a hollow shaft adapted to pass cooling water therethrough, web members on the shaft extending radially therefrom in spaced relation relative to each other, spacing means connecting the web members for supporting the web members in rigid spaced relation relative to each other, a ring peripherally secured to each web member and extending at substantially right angles from the Web members and defining flanges having an outside diameter closely conforming to the inside diameter of the tubular roll body, said rings being tapered on their underside from the web members toward their free edges, the said flanges being divided into a plurality of segments of substantially equal widths, a plurality of individual wedge members adjustably mounted on the web members, mounting instrumentalities for the wedge members including supporting brackets secured to the web members peripherally thereof, bolts passing through the web members and wedge members, the saidbolts being throughbolts spanning the space between the web members and passing therethrough and through the wedge members, the said wedge members having an arcuate surface engaging the segments of said rings for expanding the said segments against the tubular roll body member responsively to clamping movement of the wedge members towards the web members, and nuts on the through-bo1ts engaging the said wedge members for forcing the wedge members into expanding engagement with the said segments.

6. Apparatus for electroplating a rapidly moving metallic strip with a dissimilar metal, which comprises a combined conveyor and electrical contact roll connected to a supply of current, the

said strip making electrical contact with the roll by passing over and around the roll, the said roll comprising a hollow tubular roll body, a hollow shaft adapted to pass cooling water therethrough, web members on the shaft extending radially therefrom in spaced relation relative to each other, spacing means connecting the web memmembers, mounting instrumentalities for the wedge members including supporting brackets secured to the web members peripherally thereof, bolts passing through the web members and wedge members, the said bolts being stove bolts passing through each of the web members and each of the wedge members, thesaid wedge mem bers having a surface slidably engaging the segments of said rings for expanding the said segments against the tubular roll body member responsively to inward movement of the wedge members towards the web memmrs, and clamping nuts on the stove bolts engaging the said wedge members for forcing the said wedge members into expanding engagement with the said segments.

'7. A roll for conveying metal strip and conducting electric current thereto in a bath comand thereby clamping said cylinder to said webs.

' WILLI AM E. WINTERHALTER.

REFERENCES SPEED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,664,713 Strickland Apr. 3, 1928 1,670,381 Rogers May 22, 1928 2,266,347 Watson Dec. 16, 1941 I 2,439,858

Muddiman et al. Apr. 20, 1948 

